Stephen Mo Hanan, a vibrant performer who sang arias and other music as a busker in San Francisco before playing Kevin Kline’s lieutenant in the acclaimed 1981 Broadway production of “The Pirates of Penzance” and three felines in the original Broadway cast of “Cats,” died on April 3 at his home in Manhattan. He was 78.
Gary Widlund, his husband and only immediate survivor, said the cause was a heart attack.
At his audition for “Cats,” Mr. Hanan (pronounced HAN-un) told Andrew Lloyd Webber, the composer, and Trevor Nunn, the director, that he had spent several years singing and accompanying himself on a concertina at a ferry terminal at the foot of Market Street in San Francisco.
“As a matter of fact, I’ve brought my concertina,” he recalled telling Mr. Nunn in an interview with The Washington Post in 1982. “He said, ‘Give me something in Italian.’ Well, I’ve never had a problem with shyness. I sang ‘Funiculi, Funicula.’”
Mr. Hanan was ultimately cast in three parts: Bustopher Jones, a portly cat, and the dual role of Asparagus, an aging theater cat, who, while reminiscing, transforms (with help from an inflatable costume) into a former role, Growltiger, a tough pirate, and performs a parody of Puccini’s “Turandot.”
During rehearsals, Mr. Hanan kept a detailed journal, which he published in 2002 as “A Cat’s Diary.”

Mr. Hanan was cast in the original production of “Cats.” During rehearsals, he kept a detailed journal, which he later turned into a book.Credit…Smith & Kraus
In an entry about the second day of rehearsal, he described an assignment from Mr. Nunn: to “pick a cartoon cat we know of, withdraw to ourselves and prepare a vignette of that cat, then return to the circle and each in turn will present.”